@font-size:18px;
html,body{
    margin: 0;
    padding: 0;
    font-family: 'Courier New', Courier, monospace;
}
body{
    background: lightcoral;
    font-size: @font-size;
    ul{
        margin: 0;
        width: 80%;
        list-style: none;
        border: 2px solid black;
        height: 65px;
        li{
            margin: 0;
            float: left;
            padding: 15px;
            line-height: 35px;
            &:hover{
                color:green;
                font-size: @font-size+5;
            }
        }
    }
}